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IB~
Per-son. I Computer
~ACRO
Assemb I er
Vera
i
on 2.00
1-11
VIDEOI
--- 06/10/85
VIDEO DISPLAY 8105
06-10-85
1151 0124 8A FC
MOV
BH.AH
STORE IN BH
1152 0126
U3:
SCROll-UP
1153 0126 B8 060 I
MOV
AX,060lH
SCROLL ONE LI NE
1154 0129 28 C9
SUB
CX,CX
UPPER LEFT CORNER
1155 0128 86
18
MOV
DH.25-1
lOWER RIGHT ROW
1156 0120 8A
16 004A R
MOV
CL,BYTE PTR .CRT_COlS
LOWER RIGHT COLUMN
11510131 FE CA
DEC
DL
1156 0133
U4.
V
r
DEO-CALL-RETURN
1159 0133 CD 10
'NT
'OH
SCROLL UP THE SCREEN
1160 0135
us;
TTY-RETURN
1161 013558
PDP
AX
RESTORE THE CHARACTER
1162 0136 E9 012E R
"MP
VIDEO_RETURN
RETURN TO CALLER
1163
1164 0139
U6:
SET-CURSOR- INC
'NC
1165 0139 FE C6
DH
NEXT ROW
1166 0138
UT.
SET-CURSOR
1161 013B B4 02
MOV
AH,02H
1168 0130 EB F4
"MP
U4
I
ESTABLISH THE NEW CURSOR
1169
1110
r-----
CHECK FOR CONTROL CHARACTERS
1111 013F
U8.
1112 013F 14 13
U9
WAS
IT A CARRIAGE RETURN
"E
1113 0141 3C OA
CMP
AL,LF
IS
IT
A LINE FEED
1114 0143 14 13
U,O
GO TO LINE FEED
1115 0145 3C 01
CMF
AL,OlH
IT
A BEll
11160141
14 16
.JE
UII
GO TO BELL
"E
' 5
1111 0149 3C 08
CMP
AL,08H
I T A BACKSPACE
1118
014B 15 AC
"NE
UO
IF NOT A CONTROL, DISPLAY
IT
1119
1180
BACK SPACE FOUND
1181
1182 0140 OA 02
OR
Ol,DL
IS IT ALREADY AT START
OF
LINE
"E
' 5
1183 014F 14 EA
U1
SET CURSOR
11840151 4A
DEC
OX
NO
=-
,JUST MOVE IT BACK
"MP
1185 0152 EB El
U1
SET_CURSOR
1186
1181
:
-----
CARR I AGE RETURN FOUND
1788
1189 01'54
U9.
1790 0154 B2 00
MOV
DL,O
MOVE TO FIR S T
COLU~N
1791 0156 EB E3
"MP
UT
SET_CURSOR
1192
1193
1-----
LINE FEED FOUND
1194
1195 0158
UIOI
1196015880 FE
18
CMP
OH,25-1
BOTTOM
OF'
SCREEN
1197 015B 15 DC
"NE
Ub
YES. SCROLL THE SCREEN
1198 0150 EB BO
"MP
U,
NO, ,JUST SET THE CURSOR
1199
1800
;-----
BELL FOUND
180 1
1802 015F
Ull :
1803 015F B9 0533
MOV
eX,1331
o
I V
I
SOR FOR 89& HZ TONE
1804 0162
83 IF
MOV
BL,a I
SET COUNT
FOR 311
&4 SECOND FOR BEEP
1805 0164 E8 0000 E
CALL
BEEP
SOUND THE POD BELL
1806 0161 EB CC
J~P
us
TTY_RETURN
1801 0169
WRITE TTY
ENDP
1808
1-- -
-:= - - - - - --- ------ - - - - - - - - ----- - --- - -- - - - - - ----- - -- -- - - - - - - - ------- --
1809
1 LIGHT PEN
1810
;
THIS ROUTINE TESTS THE LIGHT PEN SWITCH AND THE LIGHT
181 I
I
PEN TR
1 GGER.
I F BOTH ARE SET. THE LOCAT I ON OF THE LIGHT
1812
I
PEN IS DETERMINED. OTHERWISE,
A RETURN WITH NO
INFOR~ATION
1813
IS MADE.
1814
ON EXITI
1815
~
AH
I
a
IF NO LIGHT PEN INFORMATION IS AVAILABLE
1816
BX.CX,DX ARE DESTROYED
18
t
1
IAHI
I
IF LIGHT PEN IS AVAILABLE
1818
(DH.DLI
=
ROW.COLUMN OF CURRENT LIGHT PEN POSITION
1819
(CHI
=
RASTER POSI TlON
1820
IBXI
=
BEST GUESS AT PIXEL HORIZONTAL POSITION
1821
i - - - - - - - - - - ------ -- - - - - - - - - - -- ------- - - - - - - - - - - - -- - - - - - - - - - - - - ------- - -
1822
ASSU~E
DSIDATA
1823 0769 03 03 05 05 03 03
DB
3,3,5,5,3,3,3,4
I
SUBTRACT_TABLE
1824
03 04
1825
WAIT FOR LIGHT PEN TO BE DEPRESSED
1826
1821 0111
READ LPEN
PROC
NEAR
1828 0111 B4 00
-
MOV
AH.O
SET NO LIGHT PEN RETURN CODE
1829 0113 8B 16 0063 R
MOV
OX ,(IoADDR 6845
GET BASE ADDRESS OF 6845
1830 0111 83 C2 06
ADD
OX.6
-
POINT TO STATUS REGISTER
1831 011A EC
AL,OX
GET STATUS REGISTER
1832 011B A8 04
TEST
Al,004H
TEST LIGHT PEN SWITCH
'N
1833 0110 14 03
Vb
GO
IF' YES
1834 071F E9 0803 R
V.-
A
NOT SET, RETURN
1835
"Z
""P
1836
;-----
NOW TEST FOR LIGHT PEN TRIGGER
1831
1838 0182 A8 02
V6_A:
TEST
AL,2
TEST LIGHT PEN TRIGGER
1839 0184 15 03
JNZ
VTA
RETURN WITHOUT RESETTING TRIGGER
1840 0186 E9 0800 R
V1
"MP
184!
1842
1-----
TRIGGER HAS BEEN SET. READ THE VALUE
IN
1843
1844 0189
V1A:
1845078984 10
MOV
AH,16
1 LIGHT PEN REGISTERS ON 6845
1846
1841
INPUT REGISTERS POINTED TO BY AH,
AND CONVERT TO ROW COLUMN IN IOXI
1848
1849 018B 8B 16 0063 R
NOV
OX. (IoAODR &845
ADDRESS REG I STER FOR 6845
1850 016F 8A C4
NOV
AL,AH
-
REG I STER TO READ
1851
0191 EE
OUT
OX,Al
SET
IT UP
1852 0192 EB 00
"MP
1/0 DELAY
,
..
1853 0794 42
'NC
OX
DATA REGISTER
1854 0195 EC
AL.OX
GET THE VALUE
1855 0796 8A E8
MOV
CH.Al
SAVE IN CX
1856 0198 4A
DEC
OX
ADDRESS REG I STER
' N
1851 0199 FE C4
AH
1858 019B 8A C4
MOV
AL,AH
SECOND DATA REGISTER
1859 0190 EE
OUT
DX,Al
1860 019E 42
'NC
ox
POINT TO DATA REGISTER
1861 019F EB 00
I/O DELAY
'NC
,-.
"M"
1862 07AI
EC
AL.,OX
GET SECOND OAT A VALUE
' N
18b3 01A2 8A E5
MOV
AH,CH
AX HAS INPUT VALUE
1864
VIDEO 1 5-159
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